Warning: file_get_contents(/data/phpspider/zhask/data//catemap/2/python/355.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
Python 非线性函数的爱因斯坦求和_Python_Arrays_Numpy_Graphics - Fatal编程技术网

Python 非线性函数的爱因斯坦求和

Python 非线性函数的爱因斯坦求和,python,arrays,numpy,graphics,Python,Arrays,Numpy,Graphics,我试图建立以下非线性成本函数(1)和(2) 通过使用numpy einsum函数 我试着将它们翻译成python,其中R是一个形状数组(14,3,3),而v,vt(表示等式(1)中的v')是形状数组(14,3)

我试图建立以下非线性成本函数(1)和(2)

通过使用numpy einsum函数

我试着将它们翻译成python,其中
R
是一个形状数组(14,3,3),而
v
vt
(表示等式(1)中的v')是形状数组(14,3)<分别代表
p
p'
的code>old_点和
new_点均为形状(6890,3)

现在,在计算
wRpv
wRtpv
的行中有一个错误
ValueError:操作数无法与形状(6890,14,3)(14,14,3)一起广播。
。我如何解决这个问题?非常感谢您的帮助

我现在明白了。 这就是解决方案:

def costfunc(x, old_points, new_points, weights, n_joints):
    """
    Set up non-linear cost functions by using equations from LBS:
    (1) p'_i = sum{j}(w_ji (R_j p_i + v_j))
    (2) p_i - sum{j}(w_ji (R_j p'_i + v'_j))
    where Rt denotes the transpose of R.
    :param old_points: original vertex positions
    :param new_points: transformed vertex positions
    :param weights: weight matrix obtained from spectral clustering
    :param n_joints: number of joints
    :return: non-linear cost functions as in (1), (2) to find the root of
    """

    # Extract rotations R, Rt and offsets v, v' from rv
    R = np.array([(np.array(x[j * 15:j * 15 + 9]).reshape(3, 3)) for j in range(n_joints)])
    Rt = np.array([R[j].T for j in range(n_joints)])
    v = np.array([(np.array(x[j * 15 + 9:j * 15 + 12])) for j in range(n_joints)])
    vt = np.array([(np.array(x[j * 15 + 12:j * 15 + 15])) for j in range(n_joints)])

    ## Use equations (1) and (2) for the non-linear pass.
    # R_j p_i
    Rp = np.einsum('jkl,il', R, old_points)
    # Rt_j p'_i
    Rtp = np.einsum('jkl,il', Rt, new_points)

    # R_j v'_j
    Rvt = np.array([R[i] @ vt[i] for i in range(n_joints)])
    # Rt_j v_j
    Rtv = np.array([Rt[i] @ v[i] for i in range(n_joints)])

    # w_ji (Rp_ij - Rtv_j)
    wRpv = np.einsum('ji,ijk->ik', weights, Rp - Rvt)
    # w_ji (Rtp'_ij - Rv'_j)
    wRtpv = np.einsum('ji,ijk->ik', weights, Rtp - Rtv)

    # Set up a non-linear cost function, then compute the squared norm.
    d = new_points - wRpv
    dt = old_points - wRtpv

    norm = np.linalg.norm(d, axis=1)
    normt = np.linalg.norm(dt, axis=1)

    result = np.concatenate([norm, normt])

    return np.power(result, 2)
我现在明白了。 这就是解决方案:

def costfunc(x, old_points, new_points, weights, n_joints):
    """
    Set up non-linear cost functions by using equations from LBS:
    (1) p'_i = sum{j}(w_ji (R_j p_i + v_j))
    (2) p_i - sum{j}(w_ji (R_j p'_i + v'_j))
    where Rt denotes the transpose of R.
    :param old_points: original vertex positions
    :param new_points: transformed vertex positions
    :param weights: weight matrix obtained from spectral clustering
    :param n_joints: number of joints
    :return: non-linear cost functions as in (1), (2) to find the root of
    """

    # Extract rotations R, Rt and offsets v, v' from rv
    R = np.array([(np.array(x[j * 15:j * 15 + 9]).reshape(3, 3)) for j in range(n_joints)])
    Rt = np.array([R[j].T for j in range(n_joints)])
    v = np.array([(np.array(x[j * 15 + 9:j * 15 + 12])) for j in range(n_joints)])
    vt = np.array([(np.array(x[j * 15 + 12:j * 15 + 15])) for j in range(n_joints)])

    ## Use equations (1) and (2) for the non-linear pass.
    # R_j p_i
    Rp = np.einsum('jkl,il', R, old_points)
    # Rt_j p'_i
    Rtp = np.einsum('jkl,il', Rt, new_points)

    # R_j v'_j
    Rvt = np.array([R[i] @ vt[i] for i in range(n_joints)])
    # Rt_j v_j
    Rtv = np.array([Rt[i] @ v[i] for i in range(n_joints)])

    # w_ji (Rp_ij - Rtv_j)
    wRpv = np.einsum('ji,ijk->ik', weights, Rp - Rvt)
    # w_ji (Rtp'_ij - Rv'_j)
    wRtpv = np.einsum('ji,ijk->ik', weights, Rtp - Rtv)

    # Set up a non-linear cost function, then compute the squared norm.
    d = new_points - wRpv
    dt = old_points - wRtpv

    norm = np.linalg.norm(d, axis=1)
    normt = np.linalg.norm(dt, axis=1)

    result = np.concatenate([norm, normt])

    return np.power(result, 2)